If there are any oil deposits on/in the wood, waiting won't get rid of them. I usually use acetone to clean up any surface that I have expoxied. As for prepping the wood for sealing, since I have always worked with okhume plywood, I have not had to worry about natural oils in the wood. As Mr. Nystrom has pointed out, paint thinners have oils in them and the oils won't evaporate. Once the sealer coat has been applied, a light cleaning with an acetone dampened cloth works wonders. The acetone evaporates on contact with any warm surface and leaves precious little residue of any kind.

Robert N Pruden